1. Technical Field
The present application relates to a surgical stapling device and, more particularly, to an endoscopic surgical stapling device having a tool assembly and an endoscopic body portion, wherein the tool assembly is rotatable independently of the endoscopic body portion.
2. Background of Related Art
Surgical devices having a tool assembly for grasping or clamping tissue between opposing jaw structure and then joining the tissue using surgical fasteners are well known in the art. In some such devices, a knife is provided to cut the tissue which has been joined by the fasteners. The fasteners are typically in the form of surgical staples although two part fasteners are also well known.
The above-described surgical devices typically include two elongated jaw members which are movable with respect to each other to capture or clamp tissue. One of the members carries a staple cartridge which houses a plurality of staples arranged, for example, in at least two lateral rows while the other member has an anvil that defines a surface for forming staple legs as the staples are driven from the staple cartridge. Generally, the stapling operation is effected by cam members that travel longitudinally through the staple cartridge, such that the cam members engage staple pushers to sequentially eject the staples from the staple cartridge. A knife can travel between the staple rows to longitudinally cut the stapled tissue between the rows of staples. Examples of known surgical stapling devices of this type are disclosed in U.S. Pat. Nos. 5,478,003, 6,250,532 and 6,241,139 which are incorporated herein by reference in their entirety.
In endoscopic or laparoscopic procedures, surgery is performed through small incisions or through small diameter cannulas inserted through small entrance wounds in the skin. Due to the limited degree of maneuverability of a stapling device when it is positioned through the skin or a cannula, it can be difficult for a surgeon to manipulate the tool assembly of the instrument to access and/or clamp tissue. To overcome this problem, instruments having rotatable endoscopic body portions and rotatable and/or articulatable tool assemblies have been developed and are commercially available. Although these instruments provide significant improvements in the endoscopic tool art, further improvements that may decrease the time required for surgical procedures by allowing surgeons to more quickly access tissue are desired.
U.S. Pat. No. 5,478,003 (“'003 patent”) discloses a surgical stapling device having a handle assembly, an elongated body portion and a fastener applying assembly. A first control mechanism is provided for rotating the elongated body and fastener applying assembly about the longitudinal axis of the elongated body portion. A second control mechanism is provided for articulating the fastener applying assembly about an axis substantially perpendicular to the longitudinal axis. A third control mechanism is provided for controlling independent rotation of the fastener applying assembly. Independent rotation of the fastener applying assembly is effected by a planetary gear assembly which drives a transmission axle and a flexible coupling. During operation of the third control mechanism, the fastener applying assembly has a tendency to lag behind operation of the control actuator. Although the stapling device disclosed in the '003 patent facilitates faster and easier access to the surgical site, a less complex more responsive surgical stapling device is desireable.
Accordingly, a continuing need exists in the art for a less complex endoscopic instrument having a tool assembly which is remotely positionable about multiple axes and is substantially directly responsive to operation of the control mechanism.